Roundcube Webmail before 1.6.20 and 1.7.x before 1.7.5 is affected by a remote content blocking bypass in the handling of FuncIRI attributes. rcube_washtml detected the CSS url() token with a pattern that enumerated only some of its escaped…

Roundcube Webmail before 1.6.20 and 1.7.x before 1.7.5 is affected by a remote content blocking bypass in the handling of FuncIRI attributes. rcube_washtml detected the CSS url() token with a pattern that enumerated only some of its escaped spellings, so values using other CSS escape sequences, for example \000075rl( or u\72 l(, were not recognized and remote content was loaded from an HTML message without the user's consent. Upstream fixed this in the commit “Fix remote content blocking bypass via CSS escapes in FuncIRI attributes (again)”, which resolves CSS escapes before matching and also inspects the `to`, `from` and `by` attributes.

Source published

22 Oct 2026 02:02:49 UTC

Source modified

26 Oct 2026 16:46:46 UTC

Observed here

26 Oct 2026 17:35:31 UTC

Source terms

CVE Program Terms of Use

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: cve-program · CVE Program Terms of Use. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS 3.1 · 5.3 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N